Mold for apparatus for molding pulp articles



a.' R. WILLIAMSON. MOLD'FOR APPARATUS FOR MOLDING PULF,A.RTITIMLIESE.i

APPLlCAfION FILED OCT. I6, 1919" Fammi" 1311.4, 1921.`

lnvenor. Ber' R. Williamson liquid pulp.

UNrrED ls'rArEs PATENT OFFICE..

AssreNon 'ro Karies FIBRE comrANY, y

WATERVILLE, MAINE, A CORYORATION OF MAINE.

MOLD FOR APPARATUS Application filed October 16,

To all whom t may concern:

VBe it-known that I, Bnnr It. WILLIAMSON, a citizen of the United States, residing at Fairfield, county of Somerset, tate of Maine, have invented an Improvement in Mold for Apparatus for Molding Pulp Articles, of which the following description, in connection with the accompanying ing, is a specification, like characters on the drawing representing like parts. This invention relates to; a mold to be used in the formation of articles such for example as pie lates andfbutter dishes from olds of this general character are employed in apparatus such as shown in the patent to Keyes No. 759,616 granted May 10, 1904;. Such a mold is comi posed of two hollow members, these memis removed article, then in a so 'ner face if it be a container sha necessary to bers being connected to sources of vacuum and compressed air. When the mold members are separated, one or both pass through a vat of liquid pulp pulp is sucked on member or members. bers have passed out from the vat of they are. closed together and pressure applied. Subsequently the molded layer 4of pulp then in the form of the desiredy article and dried. It is obviously important that the pulp and moist condition shall be readily removable from the mold members without injury, therwise the article is spoiled. It is also desirable that thek faces of the article, but particularly the inll be of a After the mold mempulp smooth and finished character. Heretofore in order to secure these results it has been employ a brass wire screen `or nely reticulated brass screen over the perforated face of the metal mol order to enable the pulp layer to be readily removable therefrom without injury, otherwise the moist pulp layer would stick or cling to the metal of the mold member which `it has also to use .such a screen in orderl been necessary desired finished character of to produce the surface. 4

I have discovered that a mold member made of aluminum will not stick or cling to the moist layer of pulp. I have discovered that aluminum peculiar character which is substantially non-adherent to moist pulp. I'Ience, I find Specification of Letters Patent.

lviding an aluminum mold draw-,p

'the invention will dmember in Y presents a surface of al non nonnina PULP ARTICLES.

g Patented Jan. 4, 1921'. 1919. Seal N0. 331,100.

that it is only necessary to use a screen over the perforated face of an aluminum mold member if it is desired to get that character of finish on the pulp article which a screen will produce.

This invention therefore consists in promember in forming articles from liquid pulp having an exterior pulp engaging to communicate with the chamberat the back of the mold.

The invention also consists in providing such an aluminum mold `member with a finely reticulated metal screen overlying its perforated face to form the pulp contacting surface when it is ticular finish imparted by such a screen.

These and other objects and features o appear more fully from description and drawing,

the ,accompanying and will be particularly pointed out in the claims.

for use desired to get the par- The drawings illustrate a mold of a design suitable for application to an apparatus o the type disclosed in the patent to Keyes above referred to. i

In the drawings- Figure 1 is a view chiefly in centralvertical section of the complete mold and its supports. p

Fig. 2 is an elevation looking at the Ainterior of the concave surface of the female mold member.

In the construction member is supported illustrated one mold by an arm forming'a part vof the apparatus while the other y mold member is supported by an arm which mayv be moved toward and from the arm l to effect the separation and closing a hollow head 3 having a flat surface 4: which the mold member is clamped. hollowyhead 3 is in communication with suitable ,sources of vacuum and compressed air. Thefouter end of the arm 2 likewise is provided with a hollow head 5 having a fiat surface 6 to which the other mold member is clamped and this hollow head is likewise in communication with suitable sources of vacuum and compressed air.

The mold members formV or shape depending upon the article to be formed and in the illustrated construction are of a shape toform a butter may be of any suitable s the moist pulp so mold member 7 is shaped at pond with the i11- ped rigidly d member 7 with a hollow head urality of perforaom its face to the hollow d member 7 is formed cast into the required here, it is to form the face of the article it is at it be covered with a screen such as the illustrated, and this ed in place by an ane` l() litting over the old member?. f also formed the desired her face of mold l1 is of .perforaface to the holbe partially or In the form rms the unnd hence no dish. The male its exterior face terior of the art'cle tothe hollow head 3. is hollow to commun and is provided wit tions 8 extending fr interior. This mol of aluminum vand and is clam interior or finished usually desirable th finely reticulated In rass wire screenV 9l screen is shown clamp nular clamping plat outer flange of the m n The other mold me of aluminum and is cast into espond withthe ot o be molded. This ith a plurality form to corr the article t also provided w tions 12 extendi low at the back entirely in the h shown they ng from its which may ollow head mold member 1'1 fo y ed side of the article a metal screen is necessary.

The metal screen i necessary where it i particular finish on t as above pointed o metal aluminum p termed a greasy fini of such a character t n either case s required to form a he article. I find that, ut, the surface of the resents what may be Sh o'r in other words,is hat it is non-adherent to that the molded article while still moist is readily removable from. the aluminum surface of the mold without v ject to corrosion by the action of the liquid Pula The inventionthus presents a mold member and a mold which is of great practical advantage in a pulp molding apparatus in enabling the pulp articles to be readily, accurately, and speedily molded in a. perfect condition. I Having thus describedmy invention what I claim as new and desire to secureby Leti ters Patent is- V1. A mold for `pulp articles comprising a member having a perforated face, a finely 'reticulated metal screen overlying'and f sevcured to said face and forming the pulp contacting surface, 4and a complemental member of aluminum having a perforated face itself forming a non-adherent pulp conl tacting surface.

2. An aluminum mold member for use in forming articles from liquid pulphaving an exterior non-adherent pulp engaging face perforated to communicate with the back of the member.

In testimony whereof, I have. signed my 70 name to this s ecification.

BLIZRT R. WILLIAMSON. 

